【正文】 used. Further samples were produced by subjecting the Calcoat coating and the graphite foil to a CVD treatment (samples designatedCVD in Table I) for a period of 75 h under the conditions described above. A more extensive descrip tion of the materials will be forthing in the dis cussion on the microstructures. . Erosion testing Multiparticle erosion tests were performed on a gas blast type rig, as described by Carter et al. [24]. In this apparatus the erodent particles enter the rig via an aperture in the base of an open hopper. A venturi fitted in the system allows the particles to be entrained in the pressed air ?ow. After passing through a nozzle with an 8 mm internal diameter, the particles strike the target at a standof distance of 40 mm. The target specimens had nominal dimensions 25 mm。 , is equal to the mass of positepressure of 5 kPa. (Note that the CVD of carbon in the interior of a porous medium is sometimes termed chemical vapour infiltration, CVI.) Another cladding material was graphite foil which was produced by Toyo Tanso by pressing exfoliated graphite ?akes in a rolling operation [23]. The foil is ?exible in nature and is predominantly held together by mechanical locking, as no binder is used. Further samples were produced by subjecting the Calcoat coating and the graphite foil to a CVD treatment (samples designatedCVD in Table I) for a period of 75 h under the conditions described above. A more extensive description of the materials will be forthing in the discussion on the microstructures. . Micro structural and surface observations Samples for optical microscopy were vacuum impregnated with resin and subsequently polished to a 1 lmfinish. Samples for SEM were mounted on to aluminium tabs and examined at an accelerating voltage of 20 kV. In the majority of cases, coating was not required due to the sufcient electrical conductivity of the carbon samples。一般來說 ,最大的侵蝕速率是發(fā)現(xiàn)一個(gè) 90 度 的入射角 176。結(jié)果 真空成型工藝生產(chǎn)中所使用的復(fù)合材料纖維的成層不連續(xù)導(dǎo)向 ,形成一個(gè)二維平面隨機(jī)結(jié)構(gòu) 。 在氣體淬火、可吸入顆粒物可能成為吸引氣體流 ,以及撞擊與絕緣可能導(dǎo)致材料 被 切除。 給出的結(jié)果包括穩(wěn)態(tài)侵蝕率作為函數(shù)的角度定義的條件下的沖擊。x y 平面方向垂直 ,最小導(dǎo)熱系數(shù) ,因此是最有可能被暴露在表面 的絕緣的熔爐中。進(jìn)一步的樣本產(chǎn)生不利涂料和石墨襯 多粒子 (樣本指定 CVD 的試樣 )，在 一段 75 h 上面描述的條件下。 發(fā)現(xiàn)由激光 的 方法。這個(gè)過程被重復(fù)和累積的質(zhì)量損失從 多次的循環(huán)中記錄 。在大多數(shù)情況下 ,不需要涂料由于碳樣品的電導(dǎo)率 。 這個(gè) 多粒子 是由把碳從氣態(tài)階段到涂層在 CVD爐。布是用酚醛樹脂浸漬 ,但很明顯 ,樹脂不能充分穿透光纖束。 3 結(jié)果和討論 CBCF 絕緣材料的結(jié)構(gòu) ,孔隙度的內(nèi)容的網(wǎng)絡(luò)是異常高的 ，達(dá) 87%的復(fù)合構(gòu)成的開放和互聯(lián)的 基礎(chǔ) 。然而 , 為了進(jìn)行比較研究 ， 在低密度的情況下 CBCF 基體材料 ,從一個(gè)重要的 角度 滲透 ,是保留在多孔結(jié)構(gòu)的復(fù)合材料。這個(gè)方法涉及 各行各業(yè)，即 為已知的時(shí)間長度測量線的長度 ,粒子的產(chǎn)生 光影 。在這個(gè)裝置從粒子進(jìn)入通過孔徑鉆機(jī)在基地的一個(gè)開放的 環(huán)境 。石墨油漆涂料 ,也應(yīng)用于 以 CBCF 襯底 的 。這是樹脂浸漬和隨后的吸化學(xué)氣相沉積 (CVD)。 通常 ,韌性和脆性材料具有不同的侵蝕特點(diǎn) 。由于這個(gè)原因 ,這些復(fù)合材料也被稱為碳保稅碳纖維 (CBCF)。 唯一的例外是石墨箔材料顯示角度為最大侵蝕 角度為 60176。 the porosity content of this fibre work is exceptionally high with 87% of the volume of the posite consisting of open and interconnected pores. The orientation of the fibres is evident in the micrograph in which the fibres lie preferentially in xy planes (. perpendicular to the z direction) but are random in direction within these planes. The thickness of the Calcoat colloidal graphite paint coating is variable, due to the brushing method of application, but generally is in the range 40— 60 lm (Fig. 2a). However, as a result of the